[Test] Refactored test to use utility function to get annotation instead of array indexing

[wang3820]

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Flakiness

Nondex was used to check and locate the flakiness in the test. The test can be reproduced using the following command:

mvn install -pl support/cdi -am -DskipTests
mvn -pl support/cdi test -Dtest=org.apache.shiro.cdi.AnnotatedTypeWrapperTest#removeAnnotations
mvn -pl support/cdi edu.illinois:nondex-maven-plugin:2.1.1:nondex -Dtest=org.apache.shiro.cdi.AnnotatedTypeWrapperTest#removeAnnotations

Issue

The test checks that if there is no Annotation in the RequiresGuest class and there is Annotation in SessionScoped class. It retrieves these classes by calling getDeclaredAnnotations method and fix indexing on the array returned. This creates the problem. Here is the implementation of getDeclaredAnnotations :

public Annotation[] getDeclaredAnnotations() {
     return AnnotationParser.toArray(this.annotationData().declaredAnnotations);
}
// this.annotationData().declaredAnnotationsdeclaredAnnotations is a map
Map<Class<? extends Annotation>, Annotation> declaredAnnotations = ....

Since the array is created from a hashmap, the order of elements in the output of getDeclaredAnnotations is not determinstic. Therefore, the fix indexing creates flakiness.

Fix

Since only SessionScoped and RequiresGuest are tested, those 2 classes are specificly extracted from the array instead of using indexing.

[lprimak]

@wang3820 Can you please squash the commits? Thank you!

[lprimak]

@wang3820 I have looked a little deeper into this. I believe it's a false positive actually.
The Map involved is actually an instance of LinkedHashMap so the order will never change.

Let me know if you still want me to merge this PR or just close it.
Thank you.

this may not be necessary after all

[wang3820]

@wang3820 I have looked a little deeper into this. I believe it's a false positive actually. The Map involved is actually an instance of LinkedHashMap so the order will never change.

Let me know if you still want me to merge this PR or just close it. Thank you.

Let me look deeper into this too. Nondex should never shuffle order of elements in a LinkedHashMap

[bdemers]

Let me look deeper into this too. Nondex should never shuffle order of elements in a LinkedHashMap

Even so, your change makes it obvious what is going on (e.g. looking for a specific annotation class vs just grabbing one by index)

[lprimak]

The other issue is that the test uses indexes in the whole code, not just this piece. Do we want to change the whole test to be consistent?

[wang3820]

@wang3820 I have looked a little deeper into this. I believe it's a false positive actually. The Map involved is actually an instance of LinkedHashMap so the order will never change.
Let me know if you still want me to merge this PR or just close it. Thank you.

Let me look deeper into this too. Nondex should never shuffle order of elements in a LinkedHashMap

It appears that the test is no longer flaky. I think I was testing on a older version.

[wang3820]

The other issue is that the test uses indexes in the whole code, not just this piece. Do we want to change the whole test to be consistent?

I think it's a good idea to change the whole test. This way the test is more readable.

[lprimak]

@wang3820 are you willing to take that on?

[wang3820]

@wang3820 are you willing to take that on?

Yes.

[wang3820]

@bdemers @lprimak I have changed all the tests so it is consistent.

I am rather new to this so I would really appreciate any suggestions!

[lprimak]

@wang3820 Awesome job! Thank you!
I will squash the commits and merge

[bdemers]

Thanks @wang3820!